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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <p id="demo01"></p>
    <script>
        // 综合练习1
        document.getElementById("demo01").innerHTML = "他强任他强，清风拂山岗<br>他横任他横，明月照大江<br>他自狠来他自恶，我自一口真气足<br>&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;——《九阳神功》"
        // 综合练习2
        let salary = 6500;
        let all = (6500 - 500) - (6500 - 500 - 5000) * 0.03;
        document.write("实际收入为：" + all);
        // 综合练习3
        let year = 2024;
        let judge = (year % 4 == 0 &&  year % 100 != 0)||(year % 400 ==0)
        if(judge){
            alert("2024年二月有29天")
        }else{
            alert("2024年二月没有29天")
        }
    </script>

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